Hi Iconoclastus!
First of all, WELCOME to the Forum...and your English is very good! I am going to break this down into 2 categories...
1) TENNIS ELBOW: You did the right thing by taking a long break from playing guitar. Conditions such as this can end careers if not treated properly. The most important thing is "LISTEN TO YOUR BODY." As soon as you start feeling pain, STOP and REST. Also, make sure that you use an ergonomic approach to your warm-up in terms of proper stretching and breathing (Pebber has a great video on this subject on YouTube). Massage is a good technique, and if you can, try acupuncture. I had something similar regarding the nerves in my right arm and index finger (my picking hand). I saw a chiropractor who also did acupuncture, and all symptoms were relieved withing 3 months!
2) YOUR VIDEO: Yes, using a metronome (or backing track) is always recommended. Your stamina is impressive, considering you are healing from Tennis Elbow, but the only major thing I noticed was that you pause when skipping strings. Your right hand looks really good. I think it is great that you notice that your technique will change, according to what you are playing. That is a good thing! I am not seeing too much Scalpel Picking or Sarod Picking, but as long as you are comfortable with your current technique, there's nothing wrong with it. Now, if you want to really perfect your Scalpel or Sarod techniques, you must start slow; using almost exaggerated movements. For Scalpel Picking, I choose a string other than the low or high "E" strings,. Practicing on the G or B strings, for example, will force you to keep your movements tight (I learned this when practicing tremolo exercises via my Classical Guitar pursuits -- The same philosophy works with a pick). When it comes to Sarod Picking, keep your wrist nice and loose. The movement is similar to opening a jar of peanut butter. Last, but not least, your left hand technique looks excellent.
Kudos for practicing with a clean tone, and that guitar is a BEAST (I just picked up an Ibanez RG8 that I am going to refurbish)!!
I hope my comments help -- KEEP UP THE GREAT WORK!!!